This invention relates to reciprocating slat conveyors and, more particularly, to reciprocating slat conveyors that are adapted to withstand heavy objects being dropped on them and also adapted for conveying heavy loads and difficult-to-convey materials, such as hot asphalt, for example.
U.S. Pat. No. 5,044,870, granted Sep. 3, 1991 to Raymond K. Foster, and entitled Method For Collecting And Compacting Garbage And Then Loading It Into A Road Vehicle, discloses a conveyor that is adapted for inclusion in a vault into which garbage is deposited for moving out of the vault into a transporting vehicle. The conveyor disclosed by this patent has relatively heavy-duty moveable slats that are mounted above relative to thick fixed slats that are both between and below the moveable slat. The moveable slats are V-shaped and each have a crown and opposite side portions that slope laterally outwardly and downwardly from the crown. The fixed slats are also V-shaped and each include a valley and side portions that slope laterally outwardly and upwardly from the valley. The gap between adjacent moveable slats is relatively narrow. The fixed slats carry fixed bearings on which the moveable slats slide. The moveable slats are driven by linear hydraulic motors which are positioned below the fixed slats and include connections that extend upwardly to the moveable slats.
U.S. Pat. No. 5,310,044, granted May 10, 1994 to Manfred W. Quaeck, and entitled Reciprocating Floor Conveyor Having Slats Of Varied Size And Drive System, therefore, discloses a conveyor having moveable lower slats positioned between moveable upper slats. The upper and lower slats are both substantially U-shaped in cross-section. The upper slats are supported by longitudinally extending bearings which are positioned within the slats. The lower conveyor slats are supported by bearings that are on top of transverse frame members. The embodiment disclosed in this patent is only capable of handling light loads.
There is a need for a heavy-duty slat conveyor that is supported by heavy-duty bearings that contact side edge portions of upper and lower conveyor slats. There is also a need for an improved way of connecting the upper and lower conveyor slats to linear hydraulic drive units which are provided to drive the conveyor slats back and forth along the slide bearings. It is an object of the present invention to fill these needs.
Reciprocating slat conveyors of the present invention are basically characterized by a plurality of laterally spaced apart, longitudinally extending, V-shaped upper conveyor slats and a plurality of laterally spaced apart, longitudinally extending, V-shaped bottom conveyor slats. The upper conveyor slats each have a crown and opposite side portions that slope laterally outwardly and downwardly from the crown. The side portions have lower surfaces. The lower conveyor slats are positioned between the upper conveyor slats. Each lower conveyor slat includes a valley and side portions that slope laterally outwardly and upwardly from the valley. The side portions have upper and lower surfaces. The side portions of the upper slats overhang the side portions of the lower slats. The side portions of the lower slats have outer edge portions. A plurality of slide bearings are positioned vertically between the upper and lower conveyor slats where the side portions of the upper conveyor slats overhang the side portions of the lower conveyor slats. The slide bearings have upper surfaces on which the lower surfaces of the side portions of the upper conveyor slats slide. The slide bearings are preferably connected to the outer edge portions of the side portions of the lower conveyor slats. In use, the upper and lower conveyor slats reciprocate in a longitudinal direction, and are supported for such movement by the slide bearings.
A bearing support may be positioned vertically below each slide bearing. Each upper conveyor slat may include a frame member that is connected to the upper conveyor slat and extends downwardly from it between a pair of slide bearings and a pair of bearing supports. A linear drive motor is connected to the frame member. In similar fashion, each lower conveyor slat may include a frame member that is connected to the lower conveyor slat and extends upwardly from it between a pair of slide bearings and a pair of bearing supports. A linear drive motor is connected to this frame member.
Preferably, the frame members for the upper and lower conveyor slats are elongated in the direction that the conveyor slats extend. The frame members for the upper slats each include a pair of spaced apart sidewalls and a top wall extending between and interconnecting the sidewalls. The sidewalls have lower edges that are connected to side portions of the upper conveyor slats above the bearings. In like fashion, the frame members for the lower conveyor slats are elongated in the direction that the lower conveyor slats extend. They also include a pair of spaced apart sidewalls and a top wall that extends between and interconnects the sidewalls. The sidewalls of these frame members have lower edges that are connected to the side portions of the lower conveyor slats above the bearings.
Each said linear hydraulic drive unit may be positioned endwise of its conveyor slat. Each linear hydraulic drive unit may include a fixed portion and a moveable portion. The moveable portion is connected to its conveyor slat. The frame members for the upper conveyor slats are connected to the upper conveyor slats endwise where the conveyor slats are connected to their drive units. The frame members for the lower conveyor slats are connected to the lower conveyor slats endwise of where the lower conveyor slats are connected to their drive units.
In preferred form, the side portions of the upper conveyor slats make a laterally outwardly widening acute angle with the side portions of the lower conveyor slats. This provides a laterally outwardly widening space between the conveyor slats which will make it difficult or prevent the compaction of material between the upper and lower slats.
Additional features, advantages and objects of the invention are described in the detailed description of the best mode, or preferred embodiment and/or are inherent in the structures that are illustrated and described. The general arrangements that are disclosed, the detailed descriptions, the drawings, and the claims which follow, are all parts of the description of the invention.